Biomechanical Behavior of a 3D-Printed Denture Base Material

To evaluate relevant material properties (flexural strength (σf), elastic modulus (E), water sorption (Wsp) and solubility (Wsl), and biocompatibility) of a 3D-printed resin (3D) and a heat cured acrylic resin (AR-control) used for complete denture manufacturing, testing the hypothesis that constructs from both materials would present acceptable material properties for clinical use.The σf, E, Wsp and Wsl were evaluated according to the ISO 20795-1:2013 standard, and the biocompatibility was evaluated using 3-4,5-dimethyl-thiazol-2-yl-2.5-diphenyltetrazolium bromide (MTT) and sulforhodamine B (SRB) assays. Disk-shaped specimens were fabricated and used for Wsp (n = 5), Wsl (n = 5), and biocompatibility (n = 3). Bar-shaped specimens (n = 30) were fabricated and stored in 37⁰ C distilled water for 48 hours and 6 months before flexural testing in a universal testing machine with constant displacement rate (5 ± 1 mm/min) until fracture. Data from σf, E, Wsp, Wsl and biocompatibility were statistically analyzed using Student t test (α= 0.05), Weibull analysis was also used for σf and E data.Significant differences between the two polymers were found for the evaluated material properties. Water storage for 6 months did not affect the flexural strength of 3D. Yet, the additive manufactured polymer showed inadequate flexural strength and water solubility values.Despite adequate biocompatibility and strength stability after 6 months of water storage, the additive manufactured polymer recommended for complete denture needs further development to improve the remaining material properties evaluated in this study.